301
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Colgan AM, Cameron AD, Kröger C. If it transcribes, we can sequence it: mining the complexities of host-pathogen-environment interactions using RNA-seq. Curr Opin Microbiol 2017; 36:37-46. [PMID: 28189909 DOI: 10.1016/j.mib.2017.01.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 02/07/2023]
Abstract
Host-pathogen interactions are exceedingly complex because they involve multiple host tissues, often occur in the context of normal microflora, and can span diverse microenvironments. Although decades of gene expression studies have provided detailed insights into infection processes, technical challenges have restricted experiments to single pathogenic species or host tissues. RNA-sequencing (RNA-seq) has revolutionized the study of gene expression because in addition to quantifying transcriptional output, it allows detection and characterization of all transcripts in a genome. Here, we review how refined approaches to RNA-seq are used to map the transcriptional networks that control host-pathogen interactions. These enhanced techniques include dRNA-seq and term-seq for the fine-scale mapping of transcriptional start and termination sites, and dual RNA-seq for simultaneous sequencing of host and bacterial pathogen transcriptomes. Dual RNA-seq experiments are currently limited to in vitro infection systems that do not fully reflect the complexities of the in vivo environment, thus a challenge is to develop in vivo model systems and experimental approaches that address the biological heterogeneity of host environments, followed by the integration of RNA-seq with other genome-scale datasets to identify the transcriptional networks that mediate host-pathogen interactions.
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Affiliation(s)
- Aoife M Colgan
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin, Ireland
| | - Andrew Ds Cameron
- Department of Biology, University of Regina, Regina, Saskatchewan, Canada
| | - Carsten Kröger
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin, Ireland.
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302
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Thänert R, Goldmann O, Beineke A, Medina E. Host-inherent variability influences the transcriptional response of Staphylococcus aureus during in vivo infection. Nat Commun 2017; 8:14268. [PMID: 28155859 PMCID: PMC5296661 DOI: 10.1038/ncomms14268] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 12/14/2016] [Indexed: 12/11/2022] Open
Abstract
The rise of antibiotic resistance calls for alternative strategies to treat bacterial infections. One attractive strategy is to directly target bacterial virulence factors with anti-virulence drugs. The expression of virulence traits by pathogens is, however, not constitutive but rather induced by the level of stress encountered within the host. Here we use dual RNA sequencing (RNA-seq) to show that intrinsic variability in the level of host resistance greatly affects the pathogen's transcriptome in vivo. Through analysis of the transcriptional profiles of host and pathogen during Staphylococcus aureus infection of two mouse strains, shown to be susceptible (A/J) or resistant (C57BL/6) to the pathogen, we demonstrate that the expression of virulence factors is dependent on the encountered host resistance. We furthermore provide evidence that this dependence strongly influences the efficacy of anti-virulence strategies, highlighting a potential limitation for the implementation of these strategies. Drugs inhibiting virulence factors of bacterial pathogens are under development. Here, Thänert et al. analyse the transcriptomes of host and pathogen during Staphylococcus aureus infection of two mouse strains, and show that virulence determinants are differentially expressed in different mouse strains.
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Affiliation(s)
- Robert Thänert
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Oliver Goldmann
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Andreas Beineke
- Institute for Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Eva Medina
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
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303
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New RNA-seq approaches for the study of bacterial pathogens. Curr Opin Microbiol 2017; 35:78-87. [DOI: 10.1016/j.mib.2017.01.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/09/2017] [Accepted: 01/12/2017] [Indexed: 12/17/2022]
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304
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Adams PP, Flores Avile C, Popitsch N, Bilusic I, Schroeder R, Lybecker M, Jewett MW. In vivo expression technology and 5' end mapping of the Borrelia burgdorferi transcriptome identify novel RNAs expressed during mammalian infection. Nucleic Acids Res 2017; 45:775-792. [PMID: 27913725 PMCID: PMC5314773 DOI: 10.1093/nar/gkw1180] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/18/2016] [Accepted: 11/15/2016] [Indexed: 12/28/2022] Open
Abstract
Borrelia burgdorferi, the bacterial pathogen responsible for Lyme disease, modulates its gene expression profile in response to the environments encountered throughout its tick-mammal infectious cycle. To begin to characterize the B. burgdorferi transcriptome during murine infection, we previously employed an in vivo expression technology-based approach (BbIVET). This identified 233 putative promoters, many of which mapped to un-annotated regions of the complex, segmented genome. Herein, we globally identify the 5' end transcriptome of B. burgdorferi grown in culture as a means to validate non-ORF associated promoters discovered through BbIVET. We demonstrate that 119 BbIVET promoters are associated with transcription start sites (TSSs) and validate novel RNA transcripts using Northern blots and luciferase promoter fusions. Strikingly, 49% of BbIVET promoters were not found to associate with TSSs. This finding suggests that these sequences may be primarily active in the mammalian host. Furthermore, characterization of the 6042 B. burgdorferi TSSs reveals a variety of RNAs including numerous antisense and intragenic transcripts, leaderless RNAs, long untranslated regions and a unique nucleotide frequency for initiating intragenic transcription. Collectively, this is the first comprehensive map of TSSs in B. burgdorferi and characterization of previously un-annotated RNA transcripts expressed by the spirochete during murine infection.
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Affiliation(s)
- Philip P Adams
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL 32827, USA
| | - Carlos Flores Avile
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL 32827, USA
| | - Niko Popitsch
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Ivana Bilusic
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna 1030, Austria
| | - Renée Schroeder
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna 1030, Austria
| | - Meghan Lybecker
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, CO 80918, USA
| | - Mollie W Jewett
- Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL 32827, USA
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305
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Tissue dual RNA-seq allows fast discovery of infection-specific functions and riboregulators shaping host-pathogen transcriptomes. Proc Natl Acad Sci U S A 2017; 114:E791-E800. [PMID: 28096329 DOI: 10.1073/pnas.1613405114] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Pathogenic bacteria need to rapidly adjust their virulence and fitness program to prevent eradication by the host. So far, underlying adaptation processes that drive pathogenesis have mostly been studied in vitro, neglecting the true complexity of host-induced stimuli acting on the invading pathogen. In this study, we developed an unbiased experimental approach that allows simultaneous monitoring of genome-wide infection-linked transcriptional alterations of the host and colonizing extracellular pathogens. Using this tool for Yersinia pseudotuberculosis-infected lymphatic tissues, we revealed numerous alterations of host transcripts associated with inflammatory and acute-phase responses, coagulative activities, and transition metal ion sequestration, highlighting that the immune response is dominated by infiltrating neutrophils and elicits a mixed TH17/TH1 response. In consequence, the pathogen's response is mainly directed to prevent phagocytic attacks. Yersinia up-regulates the gene and expression dose of the antiphagocytic type III secretion system (T3SS) and induces functions counteracting neutrophil-induced ion deprivation, radical stress, and nutritional restraints. Several conserved bacterial riboregulators were identified that impacted this response. The strongest influence on virulence was found for the loss of the carbon storage regulator (Csr) system, which is shown to be essential for the up-regulation of the T3SS on host cell contact. In summary, our established approach provides a powerful tool for the discovery of infection-specific stimuli, induced host and pathogen responses, and underlying regulatory processes.
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306
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Crua Asensio N, Muñoz Giner E, de Groot NS, Torrent Burgas M. Centrality in the host-pathogen interactome is associated with pathogen fitness during infection. Nat Commun 2017; 8:14092. [PMID: 28090086 PMCID: PMC5241799 DOI: 10.1038/ncomms14092] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 11/29/2016] [Indexed: 12/14/2022] Open
Abstract
To perform their functions proteins must interact with each other, but how these interactions influence bacterial infection remains elusive. Here we demonstrate that connectivity in the host-pathogen interactome is directly related to pathogen fitness during infection. Using Y. pestis as a model organism, we show that the centrality-lethality rule holds for pathogen fitness during infection but only when the host-pathogen interactome is considered. Our results suggest that the importance of pathogen proteins during infection is directly related to their number of interactions with the host. We also show that pathogen proteins causing an extensive rewiring of the host interactome have a higher impact in pathogen fitness during infection. Hence, we conclude that hubs in the host-pathogen interactome should be explored as promising targets for antimicrobial drug design.
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Affiliation(s)
- Núria Crua Asensio
- Systems Biology of Infection Lab, Department of Microbiology, Vall d'Hebron Institut de Recerca (VHIR), Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain
| | - Elisabet Muñoz Giner
- Systems Biology of Infection Lab, Department of Microbiology, Vall d'Hebron Institut de Recerca (VHIR), Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain
| | - Natalia Sánchez de Groot
- Gene Function and Evolution Lab, Centre for Genomic Regulation (CRG), Dr Aiguader 88, 08003 Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Marc Torrent Burgas
- Systems Biology of Infection Lab, Department of Microbiology, Vall d'Hebron Institut de Recerca (VHIR), Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain.,Universitat Autònoma de Barcelona, Department of Biochemistry and Molecular Biology, Biosciences Faculty, 08193 Cerdanyola del Vallès, Spain
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307
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308
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García-Del Portillo F, Pucciarelli MG. RNA-Seq unveils new attributes of the heterogeneous Salmonella-host cell communication. RNA Biol 2017; 14:429-435. [PMID: 28045572 DOI: 10.1080/15476286.2016.1276148] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
High-throughput RNA sequencing (RNA-Seq) has uncovered hundreds of small RNAs and complex modes of RNA regulation in every bacterium analyzed to date. This complexity agrees with the adaptability of most bacteria to varied environments including, in the case of pathogens, the new niches encountered in the host. Recent RNA-Seq studies have analyzed simultaneously gene expression in the intracellular pathogen Salmonella enterica and infected host cells at population and single-cell level. Distinct polarization states or interferon responses in the infected macrophage were linked to variable growth rates or activities of defined virulence regulators in intra-phagosomal bacteria. Intracellular Salmonella, however, exhibit disparate intracellular lifestyles depending the host cell, ranging from a hyper-replicative cytosolic state in epithelial cells to a non-replicative intra-phagosomal condition in varied host cell types. The basis of such diverse pathogen-host communications could be examined by RNA-Seq studies in single intracellular Salmonella cells, certainly a challenge for future investigations.
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Affiliation(s)
- Francisco García-Del Portillo
- a Laboratory of Intracellular Bacterial Pathogens, Department of Microbial Biotechnology , Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC) , Darwin, Madrid , Spain
| | - M Graciela Pucciarelli
- a Laboratory of Intracellular Bacterial Pathogens, Department of Microbial Biotechnology , Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC) , Darwin, Madrid , Spain.,b Centro de Biología Molecular Severo Ochoa (CBMSO-CSIC), Department de Molecular Biology , Universidad Autónoma de Madrid , Nicolás Cabrera, Madrid , Spain
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309
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310
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Yang P, Wang N, Wang C, Yao Y, Fu X, Yu W, Cai R, Yao M. 460nm visible light irradiation eradicates MRSA via inducing prophage activation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2017; 166:311-322. [DOI: 10.1016/j.jphotobiol.2016.12.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 12/01/2016] [Accepted: 12/03/2016] [Indexed: 12/20/2022]
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311
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Affiliation(s)
- Jens Hör
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Jörg Vogel
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany.,Helmholtz Institute for RNA-based Infection Research (HIRI), Würzburg, Germany
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312
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Bent ZW, Poorey K, LaBauve AE, Hamblin R, Williams KP, Meagher RJ. A Rapid Spin Column-Based Method to Enrich Pathogen Transcripts from Eukaryotic Host Cells Prior to Sequencing. PLoS One 2016; 11:e0168788. [PMID: 28002481 PMCID: PMC5176299 DOI: 10.1371/journal.pone.0168788] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 12/06/2016] [Indexed: 02/04/2023] Open
Abstract
When analyzing pathogen transcriptomes during the infection of host cells, the signal-to-background (pathogen-to-host) ratio of nucleic acids (NA) in infected samples is very small. Despite the advancements in next-generation sequencing, the minute amount of pathogen NA makes standard RNA-seq library preps inadequate for effective gene-level analysis of the pathogen in cases with low bacterial loads. In order to provide a more complete picture of the pathogen transcriptome during an infection, we developed a novel pathogen enrichment technique, which can enrich for transcripts from any cultivable bacteria or virus, using common, readily available laboratory equipment and reagents. To evenly enrich for pathogen transcripts, we generate biotinylated pathogen-targeted capture probes in an enzymatic process using the entire genome of the pathogen as a template. The capture probes are hybridized to a strand-specific cDNA library generated from an RNA sample. The biotinylated probes are captured on a monomeric avidin resin in a miniature spin column, and enriched pathogen-specific cDNA is eluted following a series of washes. To test this method, we performed an in vitro time-course infection using Klebsiella pneumoniae to infect murine macrophage cells. K. pneumoniae transcript enrichment efficiency was evaluated using RNA-seq. Bacterial transcripts were enriched up to ~400-fold, and allowed the recovery of transcripts from ~2000–3600 genes not observed in untreated control samples. These additional transcripts revealed interesting aspects of K. pneumoniae biology including the expression of putative virulence factors and the expression of several genes responsible for antibiotic resistance even in the absence of drugs.
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Affiliation(s)
- Zachary W. Bent
- Systems Biology Department, Sandia National Laboratories, Livermore, California, United States of America
- * E-mail: (ZWB); (RJM)
| | - Kunal Poorey
- Systems Biology Department, Sandia National Laboratories, Livermore, California, United States of America
| | - Annette E. LaBauve
- Biotechnology and Bioengineering Department, Sandia National Laboratories, Livermore, California, United States of America
| | - Rachelle Hamblin
- Systems Biology Department, Sandia National Laboratories, Livermore, California, United States of America
| | - Kelly P. Williams
- Systems Biology Department, Sandia National Laboratories, Livermore, California, United States of America
| | - Robert J. Meagher
- Biotechnology and Bioengineering Department, Sandia National Laboratories, Livermore, California, United States of America
- * E-mail: (ZWB); (RJM)
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313
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Dual-seq transcriptomics reveals the battle for iron during Pseudomonas aeruginosa acute murine pneumonia. Sci Rep 2016; 6:39172. [PMID: 27982111 PMCID: PMC5159919 DOI: 10.1038/srep39172] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/18/2016] [Indexed: 12/21/2022] Open
Abstract
Determining bacterial gene expression during infection is fundamental to understand pathogenesis. In this study, we used dual RNA-seq to simultaneously measure P. aeruginosa and the murine host’s gene expression and response to respiratory infection. Bacterial genes encoding products involved in metabolism and virulence were differentially expressed during infection and the type III and VI secretion systems were highly expressed in vivo. Strikingly, heme acquisition, ferric-enterobactin transport, and pyoverdine biosynthesis genes were found to be significantly up-regulated during infection. In the mouse, we profiled the acute immune response to P. aeruginosa and identified the pro-inflammatory cytokines involved in acute response to the bacterium in the lung. Additionally, we also identified numerous host iron sequestration systems upregulated during infection. Overall, this work sheds light on how P. aeruginosa triggers a pro-inflammatory response and competes for iron with the host during infection, as iron is one of the central elements for which both pathogen and host fight during acute pneumonia.
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314
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Saliba AE, Li L, Westermann AJ, Appenzeller S, Stapels DAC, Schulte LN, Helaine S, Vogel J. Single-cell RNA-seq ties macrophage polarization to growth rate of intracellular Salmonella. Nat Microbiol 2016; 2:16206. [PMID: 27841856 DOI: 10.1038/nmicrobiol.2016.206] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 09/16/2016] [Indexed: 01/05/2023]
Abstract
Intracellular bacterial pathogens can exhibit large heterogeneity in growth rate inside host cells, with major consequences for the infection outcome. If and how the host responds to this heterogeneity remains poorly understood. Here, we combined a fluorescent reporter of bacterial cell division with single-cell RNA-sequencing analysis to study the macrophage response to different intracellular states of the model pathogen Salmonella enterica serovar Typhimurium. The transcriptomes of individual infected macrophages revealed a spectrum of functional host response states to growing and non-growing bacteria. Intriguingly, macrophages harbouring non-growing Salmonella display hallmarks of the proinflammatory M1 polarization state and differ little from bystander cells, suggesting that non-growing bacteria evade recognition by intracellular immune receptors. By contrast, macrophages containing growing bacteria have turned into an anti-inflammatory, M2-like state, as if fast-growing intracellular Salmonella overcome host defence by reprogramming macrophage polarization. Additionally, our clustering approach reveals intermediate host functional states between these extremes. Altogether, our data suggest that gene expression variability in infected host cells shapes different cellular environments, some of which may favour a growth arrest of Salmonella facilitating immune evasion and the establishment of a long-term niche, while others allow Salmonella to escape intracellular antimicrobial activity and proliferate.
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Affiliation(s)
- Antoine-Emmanuel Saliba
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany.,Core Unit SysMed, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Lei Li
- Core Unit SysMed, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Alexander J Westermann
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Silke Appenzeller
- Core Unit SysMed, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Daphne A C Stapels
- Section of Microbiology, Medical Research Council (MRC) Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK
| | - Leon N Schulte
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Sophie Helaine
- Section of Microbiology, Medical Research Council (MRC) Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
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315
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Abstract
Small regulatory RNAs comprise critically important modulators of gene expression in bacteria, yet very little is known about their prevalence and functions in Rickettsia species. R. conorii, the causative agent of Mediterranean spotted fever, is a tick-borne pathogen that primarily infects microvascular endothelium in humans. We have determined the transcriptional landscape of R. conorii during infection of Human Microvascular Endothelial Cells (HMECs) by strand-specific RNA sequencing to identify 4 riboswitches, 13 trans-acting (intergenic), and 22 cis-acting (antisense) small RNAs (termed ‘Rc_sR’s). Independent expression of four novel trans-acting sRNAs (Rc_sR31, Rc_sR33, Rc_sR35, and Rc_sR42) and known bacterial sRNAs (6S, RNaseP_bact_a, ffs, and α-tmRNA) was next confirmed by Northern hybridization. Comparative analysis during infection of HMECs vis-à-vis tick AAE2 cells revealed significantly higher expression of Rc_sR35 and Rc_sR42 in HMECs, whereas Rc_sR31 and Rc_sR33 were expressed at similar levels in both cell types. We further predicted a total of 502 genes involved in all important biological processes as potential targets of Rc_sRs and validated the interaction of Rc_sR42 with cydA (cytochrome d ubiquinol oxidase subunit I). Our findings constitute the first evidence of the existence of post-transcriptional riboregulatory mechanisms in R. conorii and interactions between a novel Rc_sR and its target mRNA.
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316
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Kamitani M, Nagano AJ, Honjo MN, Kudoh H. RNA-Seq reveals virus-virus and virus-plant interactions in nature. FEMS Microbiol Ecol 2016; 92:fiw176. [PMID: 27549115 PMCID: PMC5854034 DOI: 10.1093/femsec/fiw176] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/10/2016] [Accepted: 08/16/2016] [Indexed: 11/17/2022] Open
Abstract
As research on plant viruses has focused mainly on crop diseases, little is known about these viruses in natural environments. To understand the ecology of viruses in natural systems, comprehensive information on virus-virus and virus-host interactions is required. We applied RNA-Seq to plants from a natural population of Arabidopsis halleri subsp. gemmifera to simultaneously determine the presence/absence of all sequence-reported viruses, identify novel viruses and quantify the host transcriptome. By introducing the criteria of read number and genome coverage, we detected infections by Turnip mosaic virus (TuMV), Cucumber mosaic virus and Brassica yellows virus Active TuMV replication was observed by ultramicroscopy. De novo assembly further identified a novel partitivirus, Arabidopsis halleri partitivirus 1 Interestingly, virus reads reached a maximum level that was equivalent to that of the host's total mRNA, although asymptomatic infection was common. AhgAGO2, a key gene in host defence systems, was upregulated in TuMV-infected plants. Multiple infection was frequent in TuMV-infected leaves, suggesting that TuMV facilitates multiple infection, probably by suppressing host RNA silencing. Revealing hidden plant-virus interactions in nature can enhance our understanding of biological interactions and may have agricultural applications.
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Affiliation(s)
- Mari Kamitani
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, Shiga 520-2113, Japan
| | - Atsushi J Nagano
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, Shiga 520-2113, Japan Faculty of Agriculture, Ryukoku University, Yokotani 1-5, Seta Oe-cho, Otsu, Shiga 520-2914, Japan JST PRESTO, Japan Science and Technology Agency, Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Mie N Honjo
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, Shiga 520-2113, Japan
| | - Hiroshi Kudoh
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, Shiga 520-2113, Japan
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317
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Hou S, Pfreundt U, Miller D, Berman-Frank I, Hess WR. mdRNA-Seq analysis of marine microbial communities from the northern Red Sea. Sci Rep 2016; 6:35470. [PMID: 27759035 PMCID: PMC5069720 DOI: 10.1038/srep35470] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/28/2016] [Indexed: 01/17/2023] Open
Abstract
Metatranscriptomic differential RNA-Seq (mdRNA-Seq) identifies the suite of active transcriptional start sites at single-nucleotide resolution through enrichment of primary transcript 5′ ends. Here we analyzed the microbial community at 45 m depth at Station A in the northern Gulf of Aqaba, Red Sea, during 500 m deep mixing in February 2012 using mdRNA-Seq and a parallel classical RNA-Seq approach. We identified promoters active in situ for five different pico-planktonic genera (the SAR11 clade of Alphaproteobacteria, Synechococcus of Cyanobacteria, Euryarchaeota, Thaumarchaeota, and Micromonas as an example for picoeukaryotic algae), showing the applicability of this approach to highly diverse microbial communities. 16S rDNA quantification revealed that 24% of the analyzed community were group II marine Euryarchaeota in which we identified a highly abundant non-coding RNA, Tan1, and detected very high expression of genes encoding intrinsically disordered proteins, as well as enzymes for the synthesis of specific B vitamins, extracellular peptidases, carbohydrate-active enzymes, and transport systems. These results highlight previously unknown functions of Euryarchaeota with community-wide relevance. The complementation of metatranscriptomic studies with mdRNA-Seq provides substantial additional information regarding transcriptional start sites, promoter activities, and the identification of non-coding RNAs.
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Affiliation(s)
- Shengwei Hou
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Ulrike Pfreundt
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Dan Miller
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Ilana Berman-Frank
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
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318
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Aprianto R, Slager J, Holsappel S, Veening JW. Time-resolved dual RNA-seq reveals extensive rewiring of lung epithelial and pneumococcal transcriptomes during early infection. Genome Biol 2016; 17:198. [PMID: 27678244 PMCID: PMC5039909 DOI: 10.1186/s13059-016-1054-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/01/2016] [Indexed: 12/02/2022] Open
Abstract
Background Streptococcus pneumoniae, the pneumococcus, is the main etiological agent of pneumonia. Pneumococcal infection is initiated by bacterial adherence to lung epithelial cells. The exact transcriptional changes occurring in both host and microbe during infection are unknown. Here, we developed a time-resolved infection model of human lung alveolar epithelial cells by S. pneumoniae and assess the resulting transcriptome changes in both organisms simultaneously by using dual RNA-seq. Results Functional analysis of the time-resolved dual RNA-seq data identifies several features of pneumococcal infection. For instance, we show that the glutathione-dependent reactive oxygen detoxification pathway in epithelial cells is activated by reactive oxygen species produced by S. pneumoniae. Addition of the antioxidant resveratrol during infection abates this response. At the same time, pneumococci activate the competence regulon during co-incubation with lung epithelial cells. By comparing transcriptional changes between wild-type encapsulated and mutant unencapsulated pneumococci, we demonstrate that adherent pneumococci, but not free-floating bacteria, repress innate immune responses in epithelial cells including expression of the chemokine IL-8 and the production of antimicrobial peptides. We also show that pneumococci activate several sugar transporters in response to adherence to epithelial cells and demonstrate that this activation depends on host-derived mucins. Conclusions We provide a dual-transcriptomics overview of early pneumococcal infection in a time-resolved manner, providing new insights into host-microbe interactions. To allow easy access to the data by the community, a web-based platform was developed (http://dualrnaseq.molgenrug.nl). Further database exploration may expand our understanding of epithelial–pneumococcal interaction, leading to novel antimicrobial strategies. Electronic supplementary material The online version of this article (doi:10.1186/s13059-016-1054-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rieza Aprianto
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Jelle Slager
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Siger Holsappel
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Jan-Willem Veening
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands. .,Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland.
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319
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Grad-seq guides the discovery of ProQ as a major small RNA-binding protein. Proc Natl Acad Sci U S A 2016; 113:11591-11596. [PMID: 27671629 DOI: 10.1073/pnas.1609981113] [Citation(s) in RCA: 204] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The functional annotation of transcriptomes and identification of noncoding RNA (ncRNA) classes has been greatly facilitated by the advent of next-generation RNA sequencing which, by reading the nucleotide order of transcripts, theoretically allows the rapid profiling of all transcripts in a cell. However, primary sequence per se is a poor predictor of function, as ncRNAs dramatically vary in length and structure and often lack identifiable motifs. Therefore, to visualize an informative RNA landscape of organisms with potentially new RNA biology that are emerging from microbiome and environmental studies requires the use of more functionally relevant criteria. One such criterion is the association of RNAs with functionally important cognate RNA-binding proteins. Here we analyze the full ensemble of cellular RNAs using gradient profiling by sequencing (Grad-seq) in the bacterial pathogen Salmonella enterica, partitioning its coding and noncoding transcripts based on their network of RNA-protein interactions. In addition to capturing established RNA classes based on their biochemical profiles, the Grad-seq approach enabled the discovery of an overlooked large collective of structured small RNAs that form stable complexes with the conserved protein ProQ. We show that ProQ is an abundant RNA-binding protein with a wide range of ligands and a global influence on Salmonella gene expression. Given its generic ability to chart a functional RNA landscape irrespective of transcript length and sequence diversity, Grad-seq promises to define functional RNA classes and major RNA-binding proteins in both model species and genetically intractable organisms.
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320
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Imam J, Singh PK, Shukla P. Plant Microbe Interactions in Post Genomic Era: Perspectives and Applications. Front Microbiol 2016; 7:1488. [PMID: 27725809 PMCID: PMC5035750 DOI: 10.3389/fmicb.2016.01488] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/07/2016] [Indexed: 01/17/2023] Open
Abstract
Deciphering plant-microbe interactions is a promising aspect to understand the benefits and the pathogenic effect of microbes and crop improvement. The advancement in sequencing technologies and various 'omics' tool has impressively accelerated the research in biological sciences in this area. The recent and ongoing developments provide a unique approach to describing these intricate interactions and test hypotheses. In the present review, we discuss the role of plant-pathogen interaction in crop improvement. The plant innate immunity has always been an important aspect of research and leads to some interesting information like the adaptation of unique immune mechanisms of plants against pathogens. The development of new techniques in the post - genomic era has greatly enhanced our understanding of the regulation of plant defense mechanisms against pathogens. The present review also provides an overview of beneficial plant-microbe interactions with special reference to Agrobacterium tumefaciens-plant interactions where plant derived signal molecules and plant immune responses are important in pathogenicity and transformation efficiency. The construction of various Genome-scale metabolic models of microorganisms and plants presented a better understanding of all metabolic interactions activated during the interactions. This review also lists the emerging repertoire of phytopathogens and its impact on plant disease resistance. Outline of different aspects of plant-pathogen interactions is presented in this review to bridge the gap between plant microbial ecology and their immune responses.
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Affiliation(s)
| | | | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand UniversityRohtak, India
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321
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Ramos-Marquès E, Zambrano S, Tiérrez A, Bianchi ME, Agresti A, García-Del Portillo F. Single-cell analyses reveal an attenuated NF-κB response in the Salmonella-infected fibroblast. Virulence 2016; 8:719-740. [PMID: 27575017 DOI: 10.1080/21505594.2016.1229727] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The eukaryotic transcriptional regulator Nuclear Factor kappa B (NF-κB) plays a central role in the defense to pathogens. Despite this, few studies have analyzed NF-κB activity in single cells during infection. Here, we investigated at the single cell level how NF-κB nuclear localization - a proxy for NF-κB activity - oscillates in infected and uninfected fibroblasts co-existing in cultures exposed to Salmonella enterica serovar Typhimurium. Fibroblasts were used due to the capacity of S. Typhimurium to persist in this cell type. Real-time dynamics of NF-κB was examined in microfluidics, which prevents cytokine accumulation. In this condition, infected (ST+) cells translocate NF-κB to the nucleus at higher rate than the uninfected (ST-) cells. Surprisingly, in non-flow (static) culture conditions, ST- fibroblasts exhibited higher NF-κB nuclear translocation than the ST+ population, with these latter cells turning refractory to external stimuli such as TNF-α or a second infection. Sorting of ST+ and ST- cell populations confirmed enhanced expression of NF-κB target genes such as IL1B, NFKBIA, TNFAIP3, and TRAF1 in uninfected (ST-) fibroblasts. These observations proved that S. Typhimurium dampens the NF-κB response in the infected fibroblast. Higher expression of SOCS3, encoding a "suppressor of cytokine signaling," was also observed in the ST+ population. Intracellular S. Typhimurium subverts NF-κB activity using protein effectors translocated by the secretion systems encoded by pathogenicity islands 1 (T1) and 2 (T2). T1 is required for regulating expression of SOCS3 and all NF-κB target genes analyzed whereas T2 displayed no role in the control of SOCS3 and IL1B expression. Collectively, these data demonstrate that S. Typhimurium attenuates NF-κB signaling in fibroblasts, an effect only perceptible when ST+ and ST- populations are analyzed separately. This tune-down in a central host defense might be instrumental for S. Typhimurium to establish intracellular persistent infections.
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Affiliation(s)
- Estel Ramos-Marquès
- a Laboratory of Intracellular Bacterial Pathogens , Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC) , Madrid , Spain
| | | | - Alberto Tiérrez
- a Laboratory of Intracellular Bacterial Pathogens , Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC) , Madrid , Spain
| | - Marco E Bianchi
- c Genetics and Cell Biology Division , San Raffaele Scientific Institute , Milan , Italy
| | - Alessandra Agresti
- c Genetics and Cell Biology Division , San Raffaele Scientific Institute , Milan , Italy
| | - Francisco García-Del Portillo
- a Laboratory of Intracellular Bacterial Pathogens , Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas (CNB-CSIC) , Madrid , Spain
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322
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Colgan AM, Kröger C, Diard M, Hardt WD, Puente JL, Sivasankaran SK, Hokamp K, Hinton JCD. The Impact of 18 Ancestral and Horizontally-Acquired Regulatory Proteins upon the Transcriptome and sRNA Landscape of Salmonella enterica serovar Typhimurium. PLoS Genet 2016; 12:e1006258. [PMID: 27564394 PMCID: PMC5001712 DOI: 10.1371/journal.pgen.1006258] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 07/25/2016] [Indexed: 11/24/2022] Open
Abstract
We know a great deal about the genes used by the model pathogen Salmonella enterica serovar Typhimurium to cause disease, but less about global gene regulation. New tools for studying transcripts at the single nucleotide level now offer an unparalleled opportunity to understand the bacterial transcriptome, and expression of the small RNAs (sRNA) and coding genes responsible for the establishment of infection. Here, we define the transcriptomes of 18 mutants lacking virulence-related global regulatory systems that modulate the expression of the SPI1 and SPI2 Type 3 secretion systems of S. Typhimurium strain 4/74. Using infection-relevant growth conditions, we identified a total of 1257 coding genes that are controlled by one or more regulatory system, including a sub-class of genes that reflect a new level of cross-talk between SPI1 and SPI2. We directly compared the roles played by the major transcriptional regulators in the expression of sRNAs, and discovered that the RpoS (σ38) sigma factor modulates the expression of 23% of sRNAs, many more than other regulatory systems. The impact of the RNA chaperone Hfq upon the steady state levels of 280 sRNA transcripts is described, and we found 13 sRNAs that are co-regulated with SPI1 and SPI2 virulence genes. We report the first example of an sRNA, STnc1480, that is subject to silencing by H-NS and subsequent counter-silencing by PhoP and SlyA. The data for these 18 regulatory systems is now available to the bacterial research community in a user-friendly online resource, SalComRegulon. The transcriptional networks and the functions of small regulatory RNAs of Salmonella enterica serovar Typhimurium are being studied intensively. S. Typhimurium is becoming the ideal model pathogen for linking transcriptional and post-transcriptional gene regulation to bacterial virulence. Here, we systematically defined the regulatory factors responsible for controlling the expression of S. Typhimurium coding genes and sRNAs under infection-relevant growth conditions. As well as confirming published regulatory inputs for Salmonella pathogenicity islands, such as the positive role played by Fur in the expression of SPI1, we report, for the first time, the global impact of the FliZ, HilE and PhoB/R transcription factors and identify 124 sRNAs that belong to virulence-associated regulons. We found a subset of genes of known and unknown function that are regulated by both HilD and SsrB, highlighting the cross-talk mechanisms that control Salmonella virulence. An integrative analysis of the regulatory datasets revealed 5 coding genes of unknown function that may play novel roles in virulence. We hope that the SalComRegulon resource will be a dynamic database that will be constantly updated to inspire new hypothesis-driven experimentation, and will contribute to the construction of a comprehensive transcriptional network for S. Typhimurium.
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Affiliation(s)
- Aoife M. Colgan
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | - Carsten Kröger
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | - Médéric Diard
- Institute of Microbiology, ETH Zürich, Zürich, Switzerland
| | | | - José L. Puente
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Cuernavaca, Morelos, Mexico
| | - Sathesh K. Sivasankaran
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | - Karsten Hokamp
- Department of Genetics, School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College, Dublin, Ireland
| | - Jay C. D. Hinton
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- * E-mail:
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323
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Khusainov I, Marenna A, Cerciat M, Fechter P, Hashem Y, Marzi S, Romby P, Yusupova G, Yusupov M. A glimpse on Staphylococcus aureus translation machinery and its control. Mol Biol 2016. [DOI: 10.1134/s002689331604004x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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324
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Fang FC, Frawley ER, Tapscott T, Vázquez-Torres A. Discrimination and Integration of Stress Signals by Pathogenic Bacteria. Cell Host Microbe 2016; 20:144-153. [PMID: 27512902 PMCID: PMC5111874 DOI: 10.1016/j.chom.2016.07.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/23/2016] [Accepted: 07/26/2016] [Indexed: 02/08/2023]
Abstract
For pathogenic bacteria, the ability to sense and respond to environmental stresses encountered within the host is critically important, allowing them to adapt to changing conditions and express virulence genes appropriately. This review considers the diverse molecular mechanisms by which stress conditions are sensed by bacteria, how related signals are discriminated, and how stress responses are integrated, highlighting recent studies in selected bacterial pathogens of clinical relevance.
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Affiliation(s)
- Ferric C Fang
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA, 98195, USA
- Department Laboratory Medicine, University of Washington School of Medicine, Seattle, WA, 98195, USA
| | - Elaine R Frawley
- Department Laboratory Medicine, University of Washington School of Medicine, Seattle, WA, 98195, USA
| | - Timothy Tapscott
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Andrés Vázquez-Torres
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045, USA
- Veterans Affairs Eastern Colorado Health Care System, 1055 Clermont Street, Denver, CO 80220, USA
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325
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Lavezzo E, Barzon L, Toppo S, Palù G. Third generation sequencing technologies applied to diagnostic microbiology: benefits and challenges in applications and data analysis. Expert Rev Mol Diagn 2016; 16:1011-23. [PMID: 27453996 DOI: 10.1080/14737159.2016.1217158] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
INTRODUCTION The diagnosis of infectious diseases is among the most successful areas of application of new generation sequencing technologies. The field has seen the development of numerous experimental and analytical approaches for the detection and the fine description of pathogenic and non-pathogenic microorganisms. AREAS COVERED Without claiming to be exhaustive with respect to all applications and methods developed over the years, this review focuses on the advantages and the issues brought by the new technologies, with an eye in particular to third generation sequencing methods. Both experimental procedures and algorithmic strategies are presented, following the most relevant publications which have led to progress in our ability of detecting infectious agents. Expert commentary: The technical advance brought by third generation sequencing platforms has the potential to significantly expand the range of diagnostic tools that will be available to clinicians. Nonetheless, the implementation of these technologies in clinical practice is still far from being actionable and will temporally follow the path undertaken by second generation methods, which still require the setup of standardized pipelines in both wet and dry laboratory procedures.
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Affiliation(s)
- Enrico Lavezzo
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| | - Luisa Barzon
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| | - Stefano Toppo
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| | - Giorgio Palù
- a Department of Molecular Medicine , University of Padova , Padova , Italy
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326
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Abstract
Enteric pathogens of the family Enterobacteriaceae colonize various niches within animals and humans in which they compete with intestinal commensals and are attacked by the host immune system. To survive these hostile environments they possess complex, multilayer regulatory networks that coordinate the control of virulence factors, host-adapted metabolic functions and stress resistance. An important part of these intricate control networks are RNA-based control systems that enable the pathogen to fine-tune its responses. Recent next-generation sequencing approaches revealed a large repertoire of conserved and species-specific riboregulators, including numerous cis- and trans-acting non-coding RNAs, sensory RNA elements (RNA thermometers, riboswitches), regulatory RNA-binding proteins and RNA degrading enzymes which regulate colonization factors, toxins, host defense processes and virulence-relevant physiological and metabolic processes. All of which are important cues for pathogens to sense and respond to fluctuating conditions during the infection. This review covers infection-relevant riboregulators of E. coli, Salmonella, Shigella and Yersinia, highlights their versatile regulatory mechanisms, complex target regulons and functions, and discusses emerging topics and future challenges to fully understand and exploit RNA-based control to combat bacterial infections.
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Affiliation(s)
- Ann Kathrin Heroven
- a Department of Molecular Infection Biology , Helmholtz Centre for Infection Research , Braunschweig , Germany
| | - Aaron M Nuss
- a Department of Molecular Infection Biology , Helmholtz Centre for Infection Research , Braunschweig , Germany
| | - Petra Dersch
- a Department of Molecular Infection Biology , Helmholtz Centre for Infection Research , Braunschweig , Germany
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327
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Avraham R, Haseley N, Fan A, Bloom-Ackermann Z, Livny J, Hung DT. A highly multiplexed and sensitive RNA-seq protocol for simultaneous analysis of host and pathogen transcriptomes. Nat Protoc 2016; 11:1477-91. [DOI: 10.1038/nprot.2016.090] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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328
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Brosse A, Korobeinikova A, Gottesman S, Guillier M. Unexpected properties of sRNA promoters allow feedback control via regulation of a two-component system. Nucleic Acids Res 2016; 44:9650-9666. [PMID: 27439713 PMCID: PMC5175337 DOI: 10.1093/nar/gkw642] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Revised: 06/21/2016] [Accepted: 07/07/2016] [Indexed: 12/22/2022] Open
Abstract
Two-component systems (TCS) and small regulatory RNAs (sRNAs) are both widespread regulators of gene expression in bacteria. TCS are in most cases transcriptional regulators. A large class of sRNAs act as post-transcriptional regulators of gene expression that modulate the translation and/or stability of target-mRNAs. Many connections have been recently unraveled between these two types of regulators, resulting in mixed regulatory circuits with poorly characterized properties. This study focuses on the negative feedback circuit that exists between the EnvZ-OmpR TCS and the OmrA/B sRNAs. We have shown that OmpR directly activates transcription from the omrA and omrB promoters, allowing production of OmrA/B sRNAs that target multiple mRNAs, including the ompR-envZ mRNA. This control of ompR-envZ by the Omr sRNAs does not affect the amount of phosphorylated OmpR, i.e. the presumably active form of the regulator. Accordingly, expression of robust OmpR targets, such as the ompC or ompF porin genes, is not affected by OmrA/B. However, we find that several OmpR targets, including OmrA/B themselves, are sensitive to changing total OmpR levels. As a result, OmrA/B limit their own synthesis. These findings unravel an additional layer of control in the expression of some OmpR targets and suggest the existence of differential regulation within the OmpR regulon.
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Affiliation(s)
- Anaïs Brosse
- CNRS UMR8261, Associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Anna Korobeinikova
- CNRS UMR8261, Associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Susan Gottesman
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maude Guillier
- CNRS UMR8261, Associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France
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329
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Fröhlich KS, Haneke K, Papenfort K, Vogel J. The target spectrum of SdsR small RNA in Salmonella. Nucleic Acids Res 2016; 44:10406-10422. [PMID: 27407104 PMCID: PMC5137417 DOI: 10.1093/nar/gkw632] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 06/11/2016] [Accepted: 06/29/2016] [Indexed: 12/28/2022] Open
Abstract
Model enteric bacteria such as Escherichia coli and Salmonella enterica express hundreds of small non-coding RNAs (sRNAs), targets for most of which are yet unknown. Some sRNAs are remarkably well conserved, indicating that they serve cellular functions that go beyond the necessities of a single species. One of these ‘core sRNAs’ of largely unknown function is the abundant ∼100-nucleotide SdsR sRNA which is transcribed by the general stress σ-factor, σS and accumulates in stationary phase. In Salmonella, SdsR was known to inhibit the synthesis of the species-specific porin, OmpD. However, sdsR genes are present in almost all enterobacterial genomes, suggesting that additional, conserved targets of this sRNA must exist. Here, we have combined SdsR pulse-expression with whole genome transcriptomics to discover 20 previously unknown candidate targets of SdsR which include mRNAs coding for physiologically important regulators such as the carbon utilization regulator, CRP, the nucleoid-associated chaperone, StpA and the antibiotic resistance transporter, TolC. Processing of SdsR by RNase E results in two cellular SdsR variants with distinct target spectra. While the overall physiological role of this orphan core sRNA remains to be fully understood, the new SdsR targets present valuable leads to determine sRNA functions in resting bacteria.
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Affiliation(s)
- Kathrin S Fröhlich
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany.,Department of Biology I, Microbiology, Ludwig-Maximilians-University Munich, D-82152 Martinsried, Germany
| | - Katharina Haneke
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
| | - Kai Papenfort
- Department of Biology I, Microbiology, Ludwig-Maximilians-University Munich, D-82152 Martinsried, Germany
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, D-97080 Würzburg, Germany
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330
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Bronesky D, Wu Z, Marzi S, Walter P, Geissmann T, Moreau K, Vandenesch F, Caldelari I, Romby P. Staphylococcus aureus RNAIII and Its Regulon Link Quorum Sensing, Stress Responses, Metabolic Adaptation, and Regulation of Virulence Gene Expression. Annu Rev Microbiol 2016; 70:299-316. [PMID: 27482744 DOI: 10.1146/annurev-micro-102215-095708] [Citation(s) in RCA: 134] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Staphylococcus aureus RNAIII is one of the main intracellular effectors of the quorum-sensing system. It is a multifunctional RNA that encodes a small peptide, and its noncoding parts act as antisense RNAs to regulate the translation and/or the stability of mRNAs encoding transcriptional regulators, major virulence factors, and cell wall metabolism enzymes. In this review, we explain how regulatory proteins and RNAIII are embedded in complex regulatory circuits to express virulence factors in a dynamic and timely manner in response to stress and environmental and metabolic changes.
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Affiliation(s)
- Delphine Bronesky
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 67084 Strasbourg, France;
| | - Zongfu Wu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Stefano Marzi
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 67084 Strasbourg, France;
| | - Philippe Walter
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 67084 Strasbourg, France;
| | - Thomas Geissmann
- Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, Université de Lyon, INSERM U1111, CNRS UMR 5308, CIRI, 69008 Lyon, France
| | - Karen Moreau
- Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, Université de Lyon, INSERM U1111, CNRS UMR 5308, CIRI, 69008 Lyon, France
| | - François Vandenesch
- Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, Université de Lyon, INSERM U1111, CNRS UMR 5308, CIRI, 69008 Lyon, France
| | - Isabelle Caldelari
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 67084 Strasbourg, France;
| | - Pascale Romby
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 67084 Strasbourg, France;
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331
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Pencik J, Pham HTT, Schmoellerl J, Javaheri T, Schlederer M, Culig Z, Merkel O, Moriggl R, Grebien F, Kenner L. JAK-STAT signaling in cancer: From cytokines to non-coding genome. Cytokine 2016; 87:26-36. [PMID: 27349799 DOI: 10.1016/j.cyto.2016.06.017] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 06/15/2016] [Indexed: 12/13/2022]
Abstract
In the past decades, studies of the Janus kinases (JAKs) and signal transducers and activators of transcription (STATs) signaling have uncovered highly conserved programs linking cytokine signaling to the regulation of essential cellular mechanisms such as proliferation, invasion, survival, inflammation and immunity. Inhibitors of the JAK/STAT pathway are used for treatment of autoimmune diseases, such as rheumatoid arthritis or psoriasis. Aberrant JAK/STAT signaling has been identified to contribute to cancer progression and metastatic development. Targeting of JAK/STAT pathway is currently one of the most promising therapeutic strategies in prostate cancer (PCa), hematopoietic malignancies and sarcomas. Notably, newly identified regulators of JAK/STAT signaling, the non-coding RNAs transcripts and their role as important targets and potential clinical biomarkers are highlighted in this review. In addition to the established role of the JAK/STAT signaling pathway in traditional cytokine signaling the non-coding RNAs add yet another layer of hidden regulation and function. Understanding the crosstalk of non-coding RNA with JAK/STAT signaling in cancer is of critical importance and may result in better patient stratification not only in terms of prognosis but also in the context of therapy.
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Affiliation(s)
- Jan Pencik
- Clinical Institute of Pathology, Medical University of Vienna, 1090 Vienna, Austria; Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, 1090 Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria.
| | - Ha Thi Thanh Pham
- Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria; Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Medical University of Vienna, 1210 Vienna, Austria
| | - Johannes Schmoellerl
- Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria
| | - Tahereh Javaheri
- Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria; Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Medical University of Vienna, 1210 Vienna, Austria
| | - Michaela Schlederer
- Clinical Institute of Pathology, Medical University of Vienna, 1090 Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria; Department for Pathology of Laboratory Animals, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Zoran Culig
- Department of Urology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Olaf Merkel
- Clinical Institute of Pathology, Medical University of Vienna, 1090 Vienna, Austria
| | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria; Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Medical University of Vienna, 1210 Vienna, Austria
| | - Florian Grebien
- Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria
| | - Lukas Kenner
- Clinical Institute of Pathology, Medical University of Vienna, 1090 Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, Medical University of Vienna, 1090 Vienna, Austria; Department for Pathology of Laboratory Animals, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
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Fröhlich KS, Papenfort K. Interplay of regulatory RNAs and mobile genetic elements in enteric pathogens. Mol Microbiol 2016; 101:701-13. [DOI: 10.1111/mmi.13428] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Kathrin S. Fröhlich
- Department of Biology I, Microbiology; Ludwig-Maximilians-University Munich; 82152 Martinsried Germany
| | - Kai Papenfort
- Department of Biology I, Microbiology; Ludwig-Maximilians-University Munich; 82152 Martinsried Germany
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Holmqvist E, Wright PR, Li L, Bischler T, Barquist L, Reinhardt R, Backofen R, Vogel J. Global RNA recognition patterns of post-transcriptional regulators Hfq and CsrA revealed by UV crosslinking in vivo. EMBO J 2016; 35:991-1011. [PMID: 27044921 PMCID: PMC5207318 DOI: 10.15252/embj.201593360] [Citation(s) in RCA: 225] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/26/2016] [Indexed: 12/22/2022] Open
Abstract
The molecular roles of many RNA‐binding proteins in bacterial post‐transcriptional gene regulation are not well understood. Approaches combining in vivo UV crosslinking with RNA deep sequencing (CLIP‐seq) have begun to revolutionize the transcriptome‐wide mapping of eukaryotic RNA‐binding protein target sites. We have applied CLIP‐seq to chart the target landscape of two major bacterial post‐transcriptional regulators, Hfq and CsrA, in the model pathogen Salmonella Typhimurium. By detecting binding sites at single‐nucleotide resolution, we identify RNA preferences and structural constraints of Hfq and CsrA during their interactions with hundreds of cellular transcripts. This reveals 3′‐located Rho‐independent terminators as a universal motif involved in Hfq–RNA interactions. Additionally, Hfq preferentially binds 5′ to sRNA‐target sites in mRNAs, and 3′ to seed sequences in sRNAs, reflecting a simple logic in how Hfq facilitates sRNA–mRNA interactions. Importantly, global knowledge of Hfq sites significantly improves sRNA‐target predictions. CsrA binds AUGGA sequences in apical loops and targets many Salmonella virulence mRNAs. Overall, our generic CLIP‐seq approach will bring new insights into post‐transcriptional gene regulation by RNA‐binding proteins in diverse bacterial species.
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Affiliation(s)
- Erik Holmqvist
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Patrick R Wright
- Bioinformatics Group, Department of Computer Science, Albert Ludwig University Freiburg, Freiburg, Germany
| | - Lei Li
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Thorsten Bischler
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Lars Barquist
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Richard Reinhardt
- Max Planck Genome Centre Cologne, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science, Albert Ludwig University Freiburg, Freiburg, Germany BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Jörg Vogel
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
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Byron SA, Van Keuren-Jensen KR, Engelthaler DM, Carpten JD, Craig DW. Translating RNA sequencing into clinical diagnostics: opportunities and challenges. Nat Rev Genet 2016; 17:257-71. [PMID: 26996076 PMCID: PMC7097555 DOI: 10.1038/nrg.2016.10] [Citation(s) in RCA: 452] [Impact Index Per Article: 56.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RNA-based measurements have the potential for application across diverse areas of human health, including disease diagnosis, prognosis and therapeutic selection. Current clinical applications include infectious diseases, cancer, transplant medicine and fetal monitoring. RNA sequencing (RNA-seq) allows for the detection of a wide variety of RNA species, including mRNA, non-coding RNA, pathogen RNA, chimeric gene fusions, transcript isoforms and splice variants, and provides the capability to quantify known, pre-defined RNA species and rare RNA transcript variants within a sample. In addition to differential expression and detection of novel transcripts, RNA-seq also supports the detection of mutations and germline variation for hundreds to thousands of expressed genetic variants, facilitating assessment of allele-specific expression of these variants. Circulating RNAs and small regulatory RNAs, such as microRNAs, are very stable. These RNA species are vigorously being tested for their potential as biomarkers. However, there are currently few agreed upon methods for isolation or quantitative measurements and a current lack of quality controls that can be used to test platform accuracy and sample preparation quality. Analytical, bioinformatic and regulatory challenges exist, and ongoing efforts toward the establishment of benchmark standards, assay optimization for clinical conditions and demonstration of assay reproducibility are required to expand the clinical utility of RNA-seq.
RNA sequencing (RNA-seq) is a powerful approach for comprehensive analyses of transcriptomes. This Review describes the widespread potential applications of RNA-seq in clinical medicine, such as detecting disease-associated mutations and gene expression disruptions, as well as characteristic non-coding RNAs, circulating extracellular RNAs or pathogen RNAs. The authors also highlight the challenges in adopting RNA-seq routinely into clinical practice. With the emergence of RNA sequencing (RNA-seq) technologies, RNA-based biomolecules hold expanded promise for their diagnostic, prognostic and therapeutic applicability in various diseases, including cancers and infectious diseases. Detection of gene fusions and differential expression of known disease-causing transcripts by RNA-seq represent some of the most immediate opportunities. However, it is the diversity of RNA species detected through RNA-seq that holds new promise for the multi-faceted clinical applicability of RNA-based measures, including the potential of extracellular RNAs as non-invasive diagnostic indicators of disease. Ongoing efforts towards the establishment of benchmark standards, assay optimization for clinical conditions and demonstration of assay reproducibility are required to expand the clinical utility of RNA-seq.
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Affiliation(s)
- Sara A Byron
- Center for Translational Innovation, Translational Genomics Research Institute, Phoenix, Arizona 85004, USA
| | | | - David M Engelthaler
- Pathogen Genomics Division, Translational Genomics Research Institute, Flagstaff, Arizona 86001, USA
| | - John D Carpten
- Integrated Cancer Genomics Division, Translational Genomics Research Institute, Phoenix, Arizona 85004, USA
| | - David W Craig
- Neurogenomics Division, Translational Genomics Research Institute, Phoenix, Arizona 85004, USA
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335
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Omics Approaches for the Study of Adaptive Immunity to Staphylococcus aureus and the Selection of Vaccine Candidates. Proteomes 2016; 4:proteomes4010011. [PMID: 28248221 PMCID: PMC5217363 DOI: 10.3390/proteomes4010011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 02/05/2016] [Accepted: 03/01/2016] [Indexed: 01/20/2023] Open
Abstract
Staphylococcus aureus is a dangerous pathogen both in hospitals and in the community. Due to the crisis of antibiotic resistance, there is an urgent need for new strategies to combat S. aureus infections, such as vaccination. Increasing our knowledge about the mechanisms of protection will be key for the successful prevention or treatment of S. aureus invasion. Omics technologies generate a comprehensive picture of the physiological and pathophysiological processes within cells, tissues, organs, organisms and even populations. This review provides an overview of the contribution of genomics, transcriptomics, proteomics, metabolomics and immunoproteomics to the current understanding of S. aureus‑host interaction, with a focus on the adaptive immune response to the microorganism. While antibody responses during colonization and infection have been analyzed in detail using immunoproteomics, the full potential of omics technologies has not been tapped yet in terms of T-cells. Omics technologies promise to speed up vaccine development by enabling reverse vaccinology approaches. In consequence, omics technologies are powerful tools for deepening our understanding of the “superbug” S. aureus and for improving its control.
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337
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Chao Y, Vogel J. A 3' UTR-Derived Small RNA Provides the Regulatory Noncoding Arm of the Inner Membrane Stress Response. Mol Cell 2016; 61:352-363. [PMID: 26805574 DOI: 10.1016/j.molcel.2015.12.023] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 11/19/2015] [Accepted: 12/16/2015] [Indexed: 12/21/2022]
Abstract
Small RNAs (sRNAs) from conserved noncoding genes are crucial regulators in bacterial signaling pathways but have remained elusive in the Cpx response to inner membrane stress. Here we report that an alternative biogenesis pathway releasing the conserved mRNA 3' UTR of stress chaperone CpxP as an ∼60-nt sRNA provides the noncoding arm of the Cpx response. This so-called CpxQ sRNA, generated by general mRNA decay through RNase E, acts as an Hfq-dependent repressor of multiple mRNAs encoding extracytoplasmic proteins. Both CpxQ and the Cpx pathway are required for cell survival under conditions of dissipation of membrane potential. Our discovery of CpxQ illustrates how the conversion of a transcribed 3' UTR into an sRNA doubles the output of a single mRNA to produce two factors with spatially segregated functions during inner membrane stress: a chaperone that targets problematic proteins in the periplasm and a regulatory RNA that dampens their synthesis in the cytosol.
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Affiliation(s)
- Yanjie Chao
- RNA Biology Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Josef-Schneider-Strasse 2, 97080 Würzburg, Germany
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Josef-Schneider-Strasse 2, 97080 Würzburg, Germany.
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